Photocomposing machine

ABSTRACT

THIS INVENTION RELATES TO PHOTOCOMPOSING AND MORE PARTICULARLY TO A PHOTOTYPESETTING MACHINE WHICH ACCEPTS CODED INPUTS SIGNALS AND AUTOMATICALLY PHOTOGRAPHS TYPE IMAGES FROM A ROTATING MASTER FONT ONTO PHOTOGRTAPHIC MATERIAL IN THE DESIRED FORMAT SUCH AS THE JUSTIFIED LINES OF TYPE USED IN NEWSPAPER TEXT. THE CHARACTER ARE SPACED BY STEPPING A PROJECTION LENS AND THE STEPPING IN CONTROLLED BY MEANS OF CHANGE GEARS TO MATCH THE REQUIREMENTS OF A READILY CHANGEABLE MASTER FRONT STRIP. STROBE CONTROL OF THE MASTER FONT CHARACTERS MOVING IN A DIRECTION PERPENDICULAR TO THE BASE LINE PROVIDES FOR ADJUSTABLE CHARACTER ALIGNMENT CONTROL.

0t 5, 1971 E. P. HANsoN ETAI- 3,610,121

PHo'rocoMPosING MACHINE Filed March 5. 1969 5 Sheets-Sheet 1 0ct. 5,1971 E. P. HANsoN l-:TAL 3,610,121

PHOTOCOMPOSING MACHINE Filed March 5, 1969 5 Sheets-Sheet 2 TOK/VEYSOct. .5, 1971 E, RHANSQN ET AL PHQTOCOMPOSING MACHINE 5 Sheets-Sheet 5Filed March 5, 1969 Mlm/mes,

Oct. 5, l1971 E, P, HANsQN ET AL PHOTOGOMPOSING MACHINE 5 Sheets-Sheet4.

Filed March 5, 1969 E www 0 i V 4 0 M5/.n M M a Ew M 6 u, .M vl

5 Sheets-Sheet 5 E. P. HANSON ETAL rHoTocoMPosING MACHINE Oct. 5, 1971Filed March 5, 1969 United States Patent O 3,610,121 PHOTOCOMPOSINGMACHINE Ellis P. Hanson, Rockport, and George J. H. Sansele,

Lynnfield, Mass., assignors to Compugraphic Corporation, Wilmington,Mass.

Filed Mar. 5, 1969, Ser. No. 804,466 Int. Cl. B41b 13/00, 15/00, 17/00U.S. Cl. 95-4.5 R 18 Claims ABSTRACT F THE DISCLOSURE One object of thisinvention is to provide a reliable, low cost and simplifiedphototypesetting machine which affords readily changeable set ups for anumber of different text typesetting functions. Another object of thisinvention is to provide a phototypesetting system which is completelycompatible with present linotype composing room operations. Yet anotherobject of this invention is to provide a control of the verticalalignment of characters so as to facilitate complex composition such asmathematical equations.

A feature of the invention relates to the manner in which the charactersare selected by counting standard TTS character codes in a unique mannerfor maximum phototypesetting speed and machine simplicity.

Another feature of the photocomposing machine relates to the positioningof the font characters on a master film strip which is accuratelymounted on a font wheel by readily detachable mountings to enable anumber of different type fonts to be selected as desired.

Another feature relates to the high speed positioning of the charactersalong a line of type by means of a stepping motor driving a projectionlens system through a pair of removable change gears related to the sizeof type.

And yet another feature of the photocomposing machine resides in thestrobing of the font characters which are rotated by a font wheel in adirection perpendicular to the character base line.

These and other objects and features of the invention will becomeapparent in the following specification and the drawings which disclosean exemplary embodiment of the invention wherein:

FIG. l is a perspective view of an assembled photocomposing machine;

FIG. 2 is a plan view of an embodiment illustrating the characterpresentation section, the projection lens assembly, and the paperadvance mechanism;

'ice

FIG. 3 is a side elevation view of the apparatus shown in FIG. 2;

FIG. 4 is a detail illustration of the font wheel assembly and the meansfor mounting the master font strip to the font wheel;

FIG. 5 is a detail illustration of the font tape showing tlliephotographic images of the characters and the timing sits;

FIG. 6 is another detail view of the font wheel and the means forsecuring the font tape to the wheel;

FIG. 7 is an enlarged sectional view of the flash lamp assembly, thefont wheel and the font timing generator; and

FIG. 8 is a block diagram representation of the computer and controlsection of the photocomposing machine.

GENERAL DESCRIPTION The apparatus of the present invention acceptsjustified or unjustified text in the form of coded characteridentification signals from any communication media such as, magnetic orpaper tape, wire connected keyboard, telephone line, etc., and providesan output generally of phototype set and justified text material to beused in the printing of newspapers, books, magazines or other similarpublications; however, the output can also be used for advertising,records, drawings, etc. However, the structure and operation of theapparatus will be understood by those having skill in the art from thefollowing detailed description with a tape input using standard 'ITScode format.

The present invention employs a well-known method of justification whichis based on the principle of assigning units of width to each characterof the typographical font and to the desired justified line lengths. Thevarious characters of the font have variable widths; however, each suchwidth is some multiple of a basic unit width, and a line length will bea much larger multiple of the same basic unit. To justify a line ofcharacters, the cumulative width units of all of the characters in aline are subtracted from the number of units in the ldesired line lengthand the remainder of units are automatically divided among the interwordspaces and letter spaces.

The photocomposer shown in FIG. l consists of two housings; lowerhousing 12 which accommodates the electronic control and computercircuitry, on printed circuit boards 14, and power supplies 16, andupper housing 18 which encloses the photo unit and provides a mountingsupport for control panel 20 and tape reader 22. Control panel 20 is notillustrated in complete detail as it forms no part of the invention;however, in a marketable photocomposer it would include any desiredmachine mode controls, start-stop switches, initializing functionswitches, such as those used to restore or reset the various computercounters and registers to zero, and input control switches such as aline length preset switch and a control to provide the desired leadingof the film advance mechanism. Tape reader 22 inputs data from punchedpaper tape of a standard format under control of the computer andvarious control panel settings. Tape readers of the type that are usedto input data to the computer of this machine are well known to the artand, consequently, no detailed description of the tape reader isnecessary to enable the invention to be practiced. Liftable doors 24,

26 provide access to the film advance mechanism and the film supply andtake-up compartments.

THE PHOTO UNIT Referring to FIG. 2, the photo unit comprises three mainsections, the character presentation system 30, the projection lensassembly 32, and the paper advance mechanism 34. The characterpresentation system includes a continuously rotating font wheel 36, axenon flash lamp 38, an optical diffuser 40, a master font strip 42, anda photocell lamp assembly or font timing generator 44. Font strip 42 hasnegative images or characters 43 of one or more complete type fonts andis attached to the surface of font Wheel 36. Timing slits or marks 37are accurately positioned alongside the font images so that as fontwheel 36 is rotating, photocell assembly 44 senses the slits to providecharacter alignment information to the computer to activate xenon flashlamp 38 at the proper instant.

Font wheel 36 is fixed to shaft 46 which is rotatably mounted in sideframes 47, 48 by bearings 49, 50. The font wheel is rotated in thedirection indicated by the arrow by motor 52 through shaft 53, pulleys54, 55 respectively mounted to shaft 53 and 46, and belt 56. Shaft 46and font wheel 36 preferably rotate at 1500 r.p.m. or at higher speeds.Font Wheel 36 is provided with flanged rim frame 58, and flash lamp 38and optical diffuser 40 are accommodated on side 59 of the font wheel36. Outer surface 60 of flanged rim frame 58 provides a flat supportingsurface for font strip 42. Flash lamp 38 and optical diffuser 40 aremounted to partition 62 by bracket 63 so as to be aligned with negativecharacters 43 on font strip 42. Font timing generator 44 is mounted topartition 62 by mounting assembly 64 so as to be aligned with the row oftiming slits 37 on font strip 42 (FIG. 8).

With reference to FIGS. 4 and 6, font wheel 36 includes a plurality offont strip guide posts, three of which, 65, 66 and 67, are shown in FIG.4,. for the purposes of accurately positioning font strip 42 on theouter surface of font wheel 36. Guide posts 65, 66, 67 project throughguide apertures y68, 69, 70 which are precisely located on font strip42. One end of font strip 42 includes metal end plate 72 having holes73, 74 which respectively engage securing pins 75, 76 mounted to block78 of font strip tensioning mechanism 80. Block 78 is mounted on thefree end of spring rod 82, the other end of which is mounted on fontwheel 36 by bracket assembly 84.

The other end of font strip 42 includes hooked end plate 86 whichengages tapered hook 88 of font wheel 36. Font strip 42 is placed on thedrum by engaging hooked end plate 86 with tapered hook 88, inserting theapertures in the font strip over guide posts 65, 66, 67 and thensecuring end plate 72 over pins 75, 76. Font strip tensioning mechanism80 provides the necessary tension to secure the font strip to the fontWheel. Finger hole 89 in flanged rim frame 58 affords a means by whichspring rod 82 may be depressed to aid in engaging or disengaging pins75, 76 from their respective apertures in end plate Font strip 42 ispreferably a strip of dimensionally stable photographic film on whichhave been developed negative timing marks 37 and negative typecharacters 43 as shown in FIGS. 4 and 5. A typical font strip will haveone-hundred-eighty (180) or more characters which is sufficient toprovide two different fonts of type on each font strip. Timing marks 37and type characters 43 are transparent, thereby -enabling light to beprojected through them. Timing marks 37 are positioned with respect tothe type characters 43 so as to provide the necessary timing signals tothe computer to enable a selected type character to be illuminated atthe proper time and projected in the proper position on the line beingset on the film as font wheel 36 rotates Continuously.

The relationship of the circuitry necessary to provide the timingindications to the computer and for projecting the image from the fontstrip to the photographic film is best illustrated with reference toFIGS. 2 and 8. Photocell assembly 44 includes lamp 90 mounted in bracket92 so as to be positioned directly behind the timing marks 37 on fontstrip 36. Spring contact 94 is mounted to support 92 by means ofinsulating member 96 and engages contact 97 of lamp 90 to provide anelectrical connection thereto. The electrical circuit to lamp iscompleted through bracket 92. Photoconductive detector 98 is mounted bysupport member 99 in partition 62, in alignment with the timing marks onthe font strip and lamp 90, and is electrically connected to photo unitcounters 238 (FIG. 8) to provide the necessary countdown in order tophotograph a selected character at the time when it appears in properposition for the xenon flash assembly as will be described more fullyhereinafter. Mask 100 is mounted over the front of photoconductivedetector 98 and is provided with aperture 101 so that a Well defined andsharp pulse is emitted by the photoconductive detector Whenever a timingmark is illuminated by lamp 90.

As described previously, xenon flash lamp 38 is mounted by bracket 63and diffuser 40 is mounted in assembly 102 so that the light emanatingfrom the flash lamp is dispersed through the font character on fontstrip 42 and then through aperture 104 in partition 62. As bestillustrated in FIG. 2, the light flashed from xenon lamp 38 is dispersedby diffuser 40 over a Wide angle which is sufficient to be picked up bythe projection lens in projection lens assembly 106 at both extreme endsof its transverse travel.

With continuing reference to FIG. 2 and additional reference to FIG. 3,projection lens assembly 32 is mounted in front of characterpresentation system 30. Projection lens 108 is rigidly fixed to carriage110 which is slidably mounted on guide rods 112, 113 held in side frames47, 48 by bearings 114-117. Carriage 110 is driven along guide rods 112,113 by stepping motor 118, gear assembly and rack 122 mounted on thecarriage. Drive gear 124 is mounted on shaft 126 of stepping motor 118by removable knurled nut 128. Stepping motor 118 is preferably SuperiorElectrics type HS-50-D, which is fluid damped or its equivalent, and issupported by platform 130. Gear 132 is driven by gear 124 and mounted onshaft 134 by removable knurled nut 136 which is interchangeable with nut128. Gears 124, 132 comprise a change gear set which provides therequired escapement for the particular size of the negative characterson the font strip. Sets of change gears having predetermined differentgear ratios may readily be installed to provide the escapements requiredby variously sized character fonts on different font strips. Shaft 134is journalled in support frame 138 and includes gear engaging teeth 142of rack 122. The aforedescribed drive assembly provides the means bywhich stepping motor 118 causes projection lens 108 to be steppedlaterally along guide rods 112, 113 to provide the proper escapement forcomposing the justified line of characters. Projection lens 108 is ahigh quality wide angle lens which receives the light rays from thecharacter illuminated by flash lamp 38 through aperture 104.

Carriage 110 includes bracket 144 having arms 145, 146 which are mountedto actuate microswitches 149, 149 fixed to partition 150. Microswitches148, 149 deenergize stepping motor 118 to limit the lateral movement ofcarriage 110, microswitch 148 providing a safety control to preventcarriage 110 from striking side frame 47 in case of normal controlfailure. Microsvvitch 149 stops carriage 110 to align the projectedcharacter image at the left margin of the line. Light shields 152, 153prevent stray light from exposing the film.

Continuing with reference to FIGS. 2 and 3, paper advance assembly 34comprises film supply box 160, film take-up box 162 and drive and guidemechanism 164 mounted therebetween. As illustrated in FIG. 2, steppingmotor 166 steps shaft 168, rotatably mounted in side frames 47, 48 bybushing 170 and coupling 172, via engaging gears 174 and 176. Gears 174,176 have a gear ratio selected to advance film 178 in one-half pointincrements. Knurled rollers 180, 181 are mounted in spaced relationshipto shaft 168 and engage flrn 178 as it passes between guide members 182and 183. Idler roller 190 is rotatably mounted on shaft 192 in line withknurled roller 180 to complete the drive mechanism for film 178. Asimilar roller, not shown, is also provided opposite knurled roller 181to provide a positive non-skewed feed of film from film supply box 160into film take-up box 162 along image plane 194. For film of narrowerwidth than the spacing between rollers 180, 181, a guide block may bemounted to guide one edge of the film, the other edge being driven byone of the paired rollers.

ELECTRONIC CONTROLS The photo composition is controlled by a computerwhich includes means for reading or sensing six-level codes in standard'ITS coding configuration on paper tape and means to process the codesby a pre-wired program to justify the text and control the photo unit tocompose the text in justified form on the photographic film. Thecornputer consists of three major sections which are the input section,the calculation section and the output section.

With reference to FIG. 8, the input section includes tape reader 22 andcontrol panel 20 (which for convenience are located on the side of thephoto unit as described above) plus reader register 200, tape readdirection control 202, position indicator counter 204, positionindicator counter register 206, and comparison circuit 208. The inputsection reads the codes for the text from the paper tape input andcontrols the direction and position of the reader. The control panelalso provides a way for the operator to control the system throughvarious switches as described above.

The calculation section includes text decoder 210, char` acter widthassignment matrix 212, pulse generator counter 214, spaceband counter216, space counter 218, Width counter 220, width count register 222,letter space character counter 224, letter space count register 226,letter space counter 228, letter space escapement counter 230, railcontrol 232, and case control 234. The calculation section counts thenumber of units of space for each character, scans for a suitable placeto end the line, and calculates the "word space and letter space valuesnecessary to justify the line to a length which has been preset into thewidth counter by the line length preset control mounted on control panel20 (FIG. 1). The control panel is illustrated in the calculater sectionof the computer only to simplify FIG. 8.

The output section consists of character identification and width gate236, photo unit counter 238, character and width control 240, stepping`motor oscillator 242, escape motor circuit 244, font timing generator44, nominal flash delay 248, and flash circuit 250. The output sectioncontrols the operation of projection lens assembly 32 (FIG. 2) toprovide the necessary escapement for projecting the font characterimages onto the film in justified relationship; controls the strobing ofthe font strip by flash lamp 38 (FIG. 2) to select the requiredcharacter from the rotating font wheel at the proper instant; andinitiates the leading of the film in preparation for a subsequentcomposition of a justified line. An important advantageous feature ofthe photocomposing machine is that ash delay 248 may be controlled bysignals from vertical alignment control 260 to adjust the strobing ofthe font strip by fiash circuit 250 to vary the vertical alignment ofthe characters so that justified lines of special characters and specialmaterial such as equations may be composed, as will be more fullydescribed hereinafter. Film advance control 252 enables the operator toselect the desired length of automatic film advance and is mounted oncontrol panel 20 (FIG. l) and is illustrated in the output section onlytov simplify FIG. 8.

6 COMPUTER CODE AND CHARACTER FONT ARRANGEMENT The detailed operation ofthe computer will be more easily understood by first describing thecharacter code used within the computer and the preferred arrangement ofthe negative characters on the font strip. The standard TTS tape uses asix-level binary code and is modified by the computer into aneight-level code by the insertion of two additional binary bits toidentify the position of each of the one hundred eighty font charactersof the font strip as well as the non-functional codes which are normallyinterposed between the character codes in the TTS coding system. Thus,as shown in Table I below, the eight-level code is obtained by insertingan additional bit between the 0 and l binary bit positions and anadditional bit following the 0 bit position of the sixlevel code. Thebit significance is also altered so that the most significant bit of thesix-level input code becomes the least significant bit (LSB) of theeight-level code. The most significant bit (MSB) of the eight-level codeis the rail bit.

LSB5 4 3 2 1 Case 0 MSB Rail The code modification is accomplished byphoto unit counter 238, rail control 232, and case control 234. Railcontrol 232 determines from text decoder 210 whether the character is inthe rst or second font/on the tape (lower rail and upper rail signals,respectively) and this information in the form of a binary 0 or l isgated to photo unit counter 238 through character identification andwidth gate 236. Similarly, case control 234 provides the necessary casebit to indicate Whether the character is upper case or lower case (shiftand unshift signals, respectively). The case and rail bits are gated atthe time the character position information is gated to photo unitcounter 238 (to be described more fully hereinafter) where theeight-level code is assembled.

The preferred arrangement of characters for one font on the font stripis illustrated in Table II below. The numbers l-l28 represent theaddress or counting position of each character and the non-functionalcodes. The significance of the counting positions, PUC 74 Negative andEnable Flash (250), in the first two bit positions will be explainedmore fully hereinafter. For each font the most commonly used charactersare positioned on the font strip before the least used characters,punctuation marks, ligatures, etc. In other words, as shown in Table IIthe lower case alphabetic characters of the first font are successivelypositioned at the beginning of the font strip followed by the upper casealphabetic characters. Then follow the numerics, ligatures and theremaining miscellaneous characters of the first font. The aforementionedorder is repeated for the characters of the second font.

The sequential order of the font characters matches the arithmetic orderof their associated binary codes. This provides for character selectionby counting to the binary value of the character being selected. Themodified TTS machine coding described herein provides for arrangement ofbasic character groups in the order of the frequency of usage of thegroups. This provides for close to optimum timing and therefore close tooptimum machine speed because the escapement mechanism gains additionaltime in which to position the projection lens for the next character tobe photographed. Furthermore, such a font character arrangementdecreases the complexity of the computer circuitry. Other arrangementsof the font characters will be apparent to those skilled in the art andthe above description is only of a preferred embodiment for purposes ofdescription and is not to be taken as limiting the scope of theinvention.

TABLE II.-CHARACTER FONT ARRANGEMENT 1. PUC74 negative 33. Unshift 65.Thin Space 2. Enable Flash (250) 34. T 66. 3 3. t 35. Return 67. P.F. orL.M. 4. Return 36. 68. 5. o 37. Space Band 69. Add Thin Space 6. SpaceBand 38. N 70. Em Space 7. n 39. H 71. 8 8. l1 40. M 72. 7 9. in 41.Elevato 73. 10. Elevato 42. I 74. 1l. i 43. R 75. 4 12. 1' 44. O 76.Boll 13. c 45. L 77. Comma 14. l 46. l 78. Quad Left 15. p 47. G 79. EnSpace 16. g 48. V 80. Q.R. 01' U M 17. V 49. E 8l. 5 18. e 50. A 82. 19.a 51. S 83. V. Rule 20. s 52. U 84. 2 2l. u 53. D 85. Em Leader 22. d54. .T 86. 6 23. j 55. F 87. 24. f 56. K 88. En Leader 25. k 57. Z 89, 926. z 58. W 90. Upper Rail 27. W 59. Y 91. 28. v 60. Q 92. Lower Rail29. q 61. B 93. Period 30. b 62. Shift 94. l 31. Shift 63. X 95. QuadCenter 32. x 64. Unshift 96. Rub Out 97. Thin Space 98. 3s

99. 1.F. or L.M. 100. l

. Add Thin Space Em Space i ll . Bell Comma 10. Quad Leit En Space itlln Leader i Upper Rail i Lower Rail 1Period Quad Center LINE BREAKDETERMINATION The computer recognizes line break points in the followingmanner. Line breaks must occur at return codes and they may occur atword spaces or discretionary hyphens. A discretionary hyphen is insertedin the input tape by the keyboard operator (in the form of a tape feedcode) and signals the computer that this is a possible break point inthe line.

ARITHMETIC OPERATIONS The computer subtracts and divides in thefollowing manner. In order to subtract, the minuend is always placed inwidth counter 220. Pulse generator counter 214 includes a clock circuit,a counter, and a gate circuit for controlling the feeding of clockpulses from the clock to the counter. The subtrahend is gated into thecounter. The counter and width counter 220 are counted down by gatedpulses from the clock until the counter in pulse generator counter 214indicates a zero count. The Value in width counter 220 is therebyreduced by the subtrahend and the difference remains in the widthcounter. Division is accomplished by a repetitive subtraction process.

COMPUTER OPERATION Initially, the operator inserts the desired linelength by setting line length preset control 23. The machine is preparedfor operation by depression of a prime switch on the control panel whichinitially sets all counters to zero, resets the registers, sets themachine in a line count mode and transfers the present line lengthinformation into width counter 220.

In the line count mode reader 22 reads the tape while it is advancing ina forward direction and the coded characters are sequentially stored inreader register 200 and decoded by text decoder 210 to generate widthvalues from character width assignment matrix 212. The widths for eachcharacter are put into pulse generator counter 214 and count pulses aregated from the aforementioned clock therein to serially subtract thecharacter or space width from width counter 220. Simultaneously, letterspace character counter 224 counts the number of letter spaceablecharacters and spaceband counter 216 counts the number of spacebandcodes (justifying word spaces) which occur in the line, Positionindicator counter 204 counts each code read from the tape to keep trackof the tape position in reader 22. During the line count mode, thecomputer continuously looks for a suitable place to end the line.

Each time that a possible line break point occurs, the number remainingin width counter 220 is transferred into width counter register 222, thecount in position indicator counter 204 is transferred into positionindicator counter register 206, and the formation in letter spacecharacter counter 244 is transferred to letter space counter register226. The transfer of the above information from the above mentionedcounters into their respective registers is nondestructive in the sensethat the count is restored to the counters so that the counters providean indication of the accumulated count and the registers are reset tozero prior to the subsequent transfer of information.

An indication of a hyphen point, for example by the reading of a tapefeed code, or by the output of a hyphenation logic circuit, which couldbe included as part of text decoder 210, would also cause theaforedescribed transfer of information. However, when width counter 220goes negative it is an indication that there is no more space left inthis particular line. At this point the numer in width count register222, representing the last possible break point in the line, istransferred back into width counter 220 in order to determine the mannerin which the extra space between Words in the line is to be distributed.The negative count in width counter 220 clears the counter and initiatesthis transfer of information as well as the clearance of letter spacecounter 224 and the transfer of information from its associatedregister. However, no information is transferred between positionindicator counter 204 and its associated register as the informationtransferred to the register at the last break point and the totalaccumulated count in the counter will be used for subsequent computercontrol functions as will be more fully described hereinafter.

Letter space comparator 239 now compares the information in spacebandcounter 216 with the information just transferred to width counter 220and, if the comparison indicates that an arbitrary difference value isnot satisfied, the computer is placed in a letter space calculate mode.A comparison exceeding the arbitrary value indicates that it isundesirable to justify the line using only spaceband expansion and theseparation between the characters in the line should also be increased;a lesser comparison value indicates that acceptable justification can beaccomplished solely by spaceband expansion and the computer is placed inan interword calculate mode to determine the necessary spacebandexpansion. In the letter space calculate mode the informationtransferred to letter space character counter 224 is subtracted from theinformation in width counter 220 and each subtraction is recorded byupdating letter space counter 22S by one count. The subtractionoperation is repeated until the arbitrary difference value is satisfiedas determined by letter space comparator 230 and the computer is placedinto an interword space calculate mode by a signal from comparator 230.

In the interwood space calculate mode the computer calculates theincrement that should be added to the basic word space value and to dothis it is necessary to divide the number of increments remaining in theline by the number of spacebands in the line which are contained inspaceband counter 216. If the computer did not enter the letter spacecalculate mode, then width counter 220 contains the number of incrementsremaining in the'line because of the transfer of information made fromregister 222 after the counter indicated a negative count. However, ifthe computer has completed a letter space calculation, then theremainder in width counter 220 after that calculation represents theline increment information used for the interword calculation. However,the presence of a hyphen in the line ending would require a subtractionof the hyphen width (six units) from width counter 220 before aninterword space calculation can be performed. The hyphen width isindicated to pulse generator counter 214 by width assignment matrix 212and the subtraction of the hyphen width and spaceband division areaccomplished as described generally above under Arithmetic Operations.Each subtraction in the division process causes space counter 218 to beadvanced by one count from a minimum spaceband value of eight, which isthe reset value of this counter and represents the desired minimumspaceband escapement. At the end of the division, indicated by the rstnegative count in width counter 220, the count in space counter 218 andthe number remaining in the counter of pulse generator counter 214 areused to effect justification as described hereinafter.

The tape direction is reversed by tape read direction control 202 whenwidth lcounter 220 indicates a negative count in the line count mode;position indicator counter 202 is directed, by tape read directioncontrol 202, to count down each code read by reader 22 until a zerocount is attained. Reader 22 is then at the beginning of the line, isstopped, and the computer enters a photograph mode. In the photographmode reader 22 reads the rst character code and then stops. Thecharacter is entered into read register 200 and decoded in text decoder210. The character position on the font strip is entered into photo unitcounter 238 via character identification and width gate 236 at the timea sync pulse is generated by font timing generator 44. Font timinggenerator 44 includes the aforedescribed photoconductive device (FIG. 8)and generates a sync pulse when the opening between thev ends of thefont strip (FIG. 4) is detected each revolution of the font wheel.Timing generator 44 outputs pulses to count down photo unit counter 238,by sensing the font strip timing marks, until the first negative countis indicated in the counter. The next timing or strobe pulse indicatesthat the desired character is positioned to be photographed and ash lamp38 (FIG. 2) is triggered by flash circuit 250 through nominal flashdelay 248.

The aforementioned operation explains the need for the two timing pulseson the font strip before the first timing pulse indicating the positionof the rst character on the font strip. These two extra timing pulsesare indicated in Table II as PUC 74 negative and Enable flash 25 0 andinsure that each font character will be accurately strobed by the ashlamp to be properly aligned in the justified line.

The vertical alignment of the character image at image plane 194 (FIG.2) may be controlled by varying the time of excitation of flash circuit250 by means of nominal flash delay 248. When setting ordinary textmaterial the illumination of the desired character is retarded after theparticular character base line timing mark is detected by a nominaldelay afforded by ash delay 248. The

various character base line timing marks are positioned on the fontstrip to account for the nominal delay so that the flash lamp istriggered to strobe the character in alignment with the base line at theimage plane. In setting special characters such as subscripts,superscripts, accent marks or in photographing equations, the requiredvertical character alignment may be established by reducing orincreasing the nominal delay. The variation of the nominal delay iscontrolled by varying the time of excitation of flash circuit 250 bymeans of input codecontrolled ash delay circuit 248. This delay circuitconsists of nine pulse generators connected in series, with the outputof each generator connected to the flash circuit through diode gating.This provides nine different time delays between the command tophotograph a character (from the photo unit counter) to the time whenthe flash circuit is actually excited.

The nominal or normal delay wherein the characters are photographed onthe baseline is taken from the fifth pulse generator and this delaysignal is gated to the flash circuit. Since the character image in theimage plane moves from below the baseline to above the baseline as thefont wheel rotates, the character may be placed in unit increments aboveor below the baseline by gating the proper pulse generator output to theflash circuit to lengthen or shorten, respectively, the time delay fromthe nominal time delay. This is accomplished by command from the inputdevice in the following manner.

An add thin code followed by a digit code (one through nine) on theinput tape signals vertical alignment control 260y that the nextcharacter to be photographed is to be placed in a discrete location withrespect to the baseline. For instance, if a character is to be placedfour units above the baseline, an add thin code followed by the digit 9code signals that the output of the ninth pulse generator is gated tothe ash circuit for the next character to be photographed thereby addingp four units of delay to the nominal value. If a character is to beplaced two units below the baseline, an add thin code followed by adigit 3 code would precede the character to be photographed and theoutput of the third pulse generator would be gated to the ash circuitgiving three units of delay or two units less than the nominal delay.

It sometimes becomes desirable to align characters vertically usingeither top of body alignment or base line alignment. This can beaccomplished by having two rows of timing slits on the font strip alongwith a separate photosensing device for each row and by selecting thedesired row of timing slits according to the type of alignment desired.A switch on the control panel allows either row to be gated to the fonttiming generator 44- (FIG. 8).

Obviously this multiple timing row technique could also be expanded toseveral rows under input code control and would then become anotherembodiment similar to tlhe pulse generator time delay system describedprevious y.

Continuing with the operation of the photographic mode, the pulse intophoto unit counter 238, which caused the flash lamp to be subsequentlytriggered, also causes reader 22 to read the next character code andactivate character and width control 240 to set character identicationwidth gate 236 to gate through the escapement width value of the strobedcharacter which is taken from width assignment matrix 212 and insertedinto photo unit counter 238. Simultaneously therewith, character' andwidth control 240 energizes stepping motor oscillator 242 which feedspulses to escape motor circuit 244 and to count-down photounit counter238. Escape motor circuit 244 activates stepping motor 118 to escapeprojection lens 108 (FIG. 2) to position it for the strobing of the nextcharacter. The foregoing procedure represents the manner in which theprojection lens is escaped for each character in the line except for thesituation where letter spacing is required and the escapement forspacebands.

If letter spacing is required, the value stored in letter space counter228, as a result of the previously described letter space calculation,must be added to the normal width value escapement of each character inthe line. This is done by transferring the value in letter space counter228 into letter space escapement counter 230 at the same time that thewidth value for the character is inserted into photo unit counter 238.Stepping motor oscillator 242 is then energized to count down letterspace escapement counter 230 to zero, while advancing escapement motor118i, before the normal width value escapement is accomplished.

The escapement for spacebands is accomplished by taking the numberstored in space counter 218, as a result of the previously describedcalculation performed in the interword space calculate mode, andwhenever a spaceband is read from the input tape this number is set intophoto unit counter 238 and escapement then continues in the normalmanner by counting down this counter by the stepping motor oscillatorpulses. When the division performed in the interword calculate mode todetermine the increments to be added to the normal spaceband results inan integral quotient, each spaceband in the line is escaped the sameincrement. However, when that division results in a non-integralquotient, it is necessary to re-distribute the spaceband increments forsome of the spacebands in order to satisfactorily justify the line.

The following example illustrates the manner in which the computerdistributes the spaceband increments for each of the spacebands in theline in the latter-mentioned situation. Assuming that thirty-oneincrements are left in width encounter 220 at the end of the line andthat tive spacebands have been counted in the line by spaceband counter216, the aforedescribed division in the interword calculate mode wouldyield a quotient of six. That is, space counter 218 would have beenupdated by six counts from its nominal value. The next subtraction inthe division process would proceed with two clock pulses gated frompulse generator counter 214 to drive width counter 220 negative, atwhich time pulse generator counter 214 would cease gating pulses. Therewould remain three counts in the counter of the pulse generator.

The spaceband escapement is performed as described above for the firstfour spacebands; the counter of pulse generator counter 214 beingcounted down by one pulse for each spaceband expansion. Therefore, onthe fourth pulse, the counter in pulse generator counter 214 will bedriven negative and a clock pulse is gated from the clock in pulsegenerator counter 214 to space counter 218, thereby increasing the spaceexpansion for the last spaceband by one to account for the singleremaining increment in the spaceband division.

The above described escapement operations continue until comparisoncircuit 208 indicates that the value counted in position indicatorcounter 204 equals the value in position indicator counter register 206.This indicates that the last character to be photographed has been readby reader 22, the reader stops, and a leading value preset in lm advanceswitch 252 is gated into photo unit counter 238. Stepping motoroscillator 242 is activated to provide pulses to count down the photounit counter as escape motor circuits 244 energize stepping motor 166(FIG. 2) to advance the lm the desired amount and also energize steppingmotor 118 to return the lens projection system to the left margin inpreparation for photographing the next line.

COMPUTER COMPONENTS The circuitry comprising each of the computercomponents is known to those skilled in the art and no detaileddescription of the circuitry is necessary, since from the aforedescribedcomputer operations, one having familiarity with the photocomposing artwould be able to construct the computer components in order to practicethe invention and they do not form a novel and unobvious part of theinvention. Similarly, the internal timing controls for carrying out thecomputer operations have not been disclosed since such timing controlswould also be apparent to one skilled in the art.

The following additional descriptive material of some of the computercomponents, however, is provided as a further aid in understanding theinvention. Text decoder 210 is simply a diode matrix and widthassignment matrix 212 also consists of a diode matrix which isconstructed in the form of a look-up table in order to provide widthvalues for the various font characters, hyphens, etc. Pulse generatorcounter 214 includes a counter which counts down in response to pulses,produced by an internal clock, which are gated by an internal gatecircuit which is controlled to insert the necessary pulses into thecounter to perform the arithmetic operations described above.

Comparison circuits 208 and 230 may consist of gate circuits, which arewell known in the art, assembled to provide the aforedescribedcomparison functions. Rail control 232, case control 234 and characterand width control 240 are preferably ip-flop circuits which are set orreset in accordance with rail or case input signals to accomplish theirabove described functions. Line length preset control 23 and filmadvance control 252 may preferably consist of manually operated counterswhich are capable of transferring their preset information by electricalpulses on command. Such manual controls are well known to those skilledin the art. Character identication and width gate 236 may merely be anassemblage of AND/OR gates to carry out the described switching functionof the character identification position information and the widthvalues into photo unit counter 238. Photo unit counter 238 must have thecapacity to store the eight-level bit code used by the computer and mustalso include the necessary logic to gate the control signals to ashcircuit 248, escape motor circuit 244 and character and width control240 when its various registers have attained the aforedescribed states.The construction of photo unit counter 238 is readily apparent to thosehaving skill in the art from the foregoing description of its operation.

Flash delay 248 may preferably consist of any electronic means which areknown to the art to delay an electrical signal and which may be variedin accordance with electrical input signals to provide a desired delayin response thereto. Stepping motor oscillator 242 is a 40() cycleoscillator to provide counting pulses and to energize escape motorcircuit 244. Escape motor circuit 244 is merely a drive circuit whichamplifies and shapes the stepping motor oscillator pulses to provide thenecessary energization of the projection lens escapement step motor andthe film advance step motor.

MODIFICATIONS OF THE PHOTOCOMPOSING MACHINE A memory could also beincluded with the tape reader so that the tape need not return to thebeginning of the line to read the tape a second time in order tophotograph the characters. This memory would have sufficient storage toaccommodate at least one line of coded information, the character codescould be stored during the line count mode and retrieved from memory inthe photographic mode and utilized in a manner similar to that describedabove.

Those skilled in the art will also recognize that the aforedescribedphotocomposing machine may also compose justified text from codedcharacter identification signals transmitted to the computer overtelephone communication channels, wire service lines, or any other meansof communication equipment. In such instances, the tape reader would 4bereplaced by input equipment compatible with the communication mediabeing used. The input equipment would require storage capabilities forretaining the coded character input signals and the individual charactercodes retrieved from storage so that the Computex would operatesubstantially as described above.

13 It is further understood that various changes and modifications maybe made in the embodiment of the invention illustrated and describedherein without departing from the scope of the invention as defined bythe subjoined claims. Having thus described the invention, what isclaimed as new and desired to be secured by Letters Patent is:

1. A photocomposing machine for receiving coded character identificationsignals and forming justified lines of text, comprising:

means for receiving the coded character identification signals, v

means for determining justified text from the coded characteridentification signals,

means for presenting font characters representing th coded signals in asequence related to the numerical value of the coded characteridentification signals,

means for strobing saidy means for presenting to select characterstherefrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship, and means for recording theprojected font characters.

2. A photocomposing machine -for receiving coded characteridentification signals and forming justified lines of text, comprising:

means for receiving the coded character identification signals,

means for determining justified text from the coded characteridentification signals,

means for presenting font characters representing the coded signals,

means for strobing said means for presenting to select characterstherefrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship, means for recording the projectedfont characters, and means for controlling said means for strobing tovary the vertical alignment of said `font characters at said imageplane.

3. A photocomposing machine according to claim 1 further comprisingmeans for modifying the input character identification code Abyinterposing bits representing case and rail character groupings in theinput code.

4. A photocomposing machine for receiving coded character identificationsignals and forming justified lines of text, comprising;

means for receiving the coded character identification signals,

means for determining justified text from the coded characteridentification signals,

means for presenting font characters representing the coded signals,

means for strobing said means for presenting to select characterstherfrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship, means for recording the projectedfont characters,

said means for presenting font characters includes timing slitspositioned to indicate the proper alignment of the individual fontcharacters and non-strobing code markings interposed between said timingslits, and the photocomposing machine further comprises means forinhibiting said means for projecting upon sensing said non-strobing codemarkings.

5. A photocomposing machine according to claim 1 wherein said means forstrobing includes means for storing the address of the font charactersto be selected from said means for presenting and means for sensing saidtiming slits to provide counting signals, said means for storingincluding means Vfor counting and is responsive to said counting signalsto cause said means for projecting to project the selected character atthe proper instant to said means for recording.

y6. A photocomposing machine for receiving coded characteridentification signals and forming justified lines of text, comprising;

means for receiving the coded character identification signals,

means for determining justified text from the coded characteridentification signals,

means for presenting front characters representing the coded signals,

means for strobing said means for presenting to select characterstherefrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship,

means for recording the projected font characters,

said means for projecting includes a projection lens movably mountedbetween said image plane and said strobing means to traverse parallel tosaid character base line, means for escaping said projection lens toposition the selected characters on said means for recording the fontcharacters in justied relationship, means for stepping said means foresca-ping in accordance with said means for determining justified text,and said means for escaping including a removably mounted change gearset having a gear ratio selected in accordance with the size of the font4characters presented to said means for projecting.

7. A photocomposing machine for receiving coded character identificationsignals and forming justified lines of text, comprising;

means for receiving the coded character identification signals,

means for determining justified text from the coded -characteridentification signals,

means for presenting font characters representing the coded signals,

means for strobing said means for 'presenting to select characterstherefrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship,

means for recording the projected font characters,

said means for presenting font characters includes a rotatable framesupport, said frame support including guide posts, a font stripincluding guide apertures for receiving said guide posts to mount saidfont strip to said frame support, said font strip including negativefont characters and timing slits located along respective opposite sidesof said font strip so that a selected timing slit indicates the requiredvertical character alignment relative to the base line of a respectivefont character, said font strip being mounted to said frame support sothat said font characters are aligned with said projecting means andsaid timing slits are in position to be sensed by said strobing means,

one end of said font strip includes means for engaging said framesupport and the other end of said font strip includes apertures, andsaid frame support further includes resilient means engaging the endapertures to secure said font strip to said frame support.

8. A 'photocomposing machine -for receiving coded characteridentification signals and forming justified lines of text, comprising;

means for receiving the coded character identification signals,

means for determining justified text from the coded characteridentification signals,

means for presenting font characters representing the coded characters,said character presentation means continuously rotating in a fixed pathperpendicular to a character base line,

means for strobing said means for presenting to select characterstherefrom in accordance with said means for determining justified text,

means for projecting said selected font characters to an image plane inaligned and justified relationship,

means to provide said character base line and for recording theprojected fon-t characters,

means for controlling said means for strobing to vary the verticalalignment of said font characters at said image plane,

means for modifying the input character identification signals byinterposing bits representing case and rail character groupings in thereceived identification signals, said means for presenting fontcharacters includes means for retaining said font characters so that themost used font characters are made available to said means for strobingbefore the least used font characters during each revolution of saidcharacter presentation means, timing slits positioned to indicate theproper alignment of the individual font characters with said characterbase line, and nonstrobing code markings interposed between said timingslits, the photocomposing machine further comprises means for inhibitingsaid means for projecting upon sensing said non-strobing code markings,

said means for projecting the selected font characters includes aprojection lens movably mounted between said image plane and saidstrobing means to traverse parallel to said character base line, meansfor escaping said projection lens to position the selected fontcharacters on said means for receiving the font characters in justifiedrelationship, means for stepping said means for escaping in accordancewith said means for determining justified text, said means for escapingincluding a removably mounted change gear set having a gear ratioselected in accordance with the size of the font characters presented tosaid means for projecting.

9. In a photocomposing machine for forming justified text from codedcharacter identification signals of the type wherein selected fontcharacters are projected onto and received by photographic filmpositioned at an image plane, the means for projecting the fontcharacters, comprising;

a projection lens movably mounted to traverse parallel to a characterbase line,

means for escaping said projection lens to position the selected fontcharacters on the photographic film in justified relationship,

means for stepping said means for escaping, and

said means for escaping including a removably mounted change gear sethaving a gear ratio selected in accordance with the size of the selectedfont characters.

10. In a photocomposing machine for forming justified text from codedcharacter identification signals of the type wherein selected fontcharacters are projected onto and received by photographic lm positionedto provide a character base line at an image plane, the means forpresentingY font characters, comprising;

frame means continuously rotating,

font strip means mounted on said frame means and including negative fontcharacters and timing slits each located along respective opposite sidesof the 16 font strip so that a selected timing slit indicates therequired vertical character alignment relative to the character baseline of a respective font character, and

wherein one end of said font strip includes means for engaging saidframe means, the other end of said font strip includes additionalapertures, and said frame means further includes resilient meansengaging said additional apertures to secure said font strip on saidframe means.

11. A photocomposing machine according to claim 2 wherein said controlmeans is responsive to coded signals representing a change in theposition of the vertical alignment ofthe characters.

12. A photocomposing machine according to claim 11 wherein said controlmeans is a delay circuit for providing time delays representingdifferent vertical alignments of said font characters at said imageplane.

13. A photocomposing machine according to claim 11 wherein said meansfor presenting font characters includes timing slits positioned withrespect to said font characters to provide control signals representingdifferent vertical alignments of said font charac-ters at said imageplane.

14. A photocomposing machine as in claim 13 wherein said timing slitsare divided into two groups, one of said groups representing top of bodyalignment and the other group representing base line alignment.

15. A photocomposing machine according to claim 12 wherein saiddifferent vertical alignments vary from top of body alignment to baseline alignment.

16. A photocomposing machine as in claim 7 wherein said means forengaging is a hooked end clip and said frame support further includes ahooked end plate for receiving and retaining said hooked end clip.

17. A photocomposing machine as in claim 16 wherein said one end of saidfont strip is folded, said hooked end clip has a bent end portion forretaining said folded end and attaching said font strip end to saidhooked end clip.

18. A photocomposing machine as in claim 6 wherein said means forpresenting font characters includestiming slits positioned to indicatethe proper alignment of the individual font characters with saidcharacter base line and non-strobing code markings interposed betweensaid timing slits, and

the photocomposing machine further comprises means for inhibiting saidmeans for projecting upon sensing said non-strobing code markings.

References Cited UNITED STATES PATENTS 3,336,849 8/1967 Broglio4 95-4.53,485,150 12/1969 Tortoriciet al. 95-4.5

SAMUEL S.`MATTHEWS, Primary Examiner R. A. WINTERCORN, AssistantExaminer Us. c1. XR.

